1. Field of the Invention
The invention relates to a hand-operated stamp comprising a partially open-pored printing plate which is displaceable against a spring force from a resting position, in which it is retracted in a housing, into a printing position by means of an actuating unit, said printing plate resting on an ink storage member so as to receive stamping ink therefrom, said ink storage member being mounted in a retaining means which at least partially encloses the former.
Furthermore, the invention relates to an ink storage member unit for storing stamping ink for a partially open-pored printing plate of such a pre-inked stamp, comprising an ink storage member mounted in a retaining means enclosing the latter.
2. The Prior Art
Hand-operated stamps as initially mentioned are commonly termed pre-inked stamps. The stamping ink required for generating the stamping imprints is stored in the storage member which transfers the stamping ink to the stamping plate. The storage member may be based on the most varying technologies, such as a salt-washout process, a gel-system or a method using a foamed material (foamed vinyl material), yet the gel system has proved to be particularly advantageous. It is, however, also possible to integrate printing plate and storage member in one single element which contains the stamping ink to be imprinted (cf. e.g. U.S. Pat. No. 6,360,661 B1), yet in that case the production is comparatively complex.
In a more recent method, the so-called flash system, in an open-pored foamed material, such as, e.g., EVA (ethylene vinyl acetate), in those areas where no stamping imprint is to be made, a closing of the pores of the open-pored material is caused, so as to produce a unique printing plate, by short-term exposures (“flash”—in particular with the help of xenon lamps); on the other hand, in those areas in which a stamping imprint is to be made, the pores of the printing plate will remain open. In order to apply the desired image for the stamping imprint to the stamping plate blanks, previously cut EVA plates are inserted in an exposing device, i.e. together with a film which has the desired stamp imprint image which, e.g., has been made by means of a computer. By a single or repeated flash-like illumination, the printing plate is produced. For its operation, this EVA printing plate must then be supplied with stamping ink, for which the storage member, in particular the foamed PVA material (pre-)inked with the stamping ink is used.
Usually, such storage members are provided in bag packages. When the storage member, i.e. the pre-inked PVA material, is removed from the package and inserted in the stamp, this as a rule is not possible without soiling: Already when cutting open the package, the cutting tool (scissors, e.g.) is soiled by stamping ink, and subsequently, such soiling is also unavoidable for tweezers or a similar tool which will be used for removing the PVA material from the package and inserting it in the stamp housing.
DE 2 152 324 A describes a hand stamp having a porous stamping block and a storage member within a frame in a retaining means. What is disadvantageous here is the refilling of ink, since complete refilling of the storage member is only possible after a removal of the handle and a cover area with a protective film, since the filling piece is configured to be at the center.
From WO 02/28658 A, a hand-operated stamp is known which has a pre-inked, single-piece stamping plate arranged in a retaining means. What is disadvantageous here i.a. is that there is no storage member separate from the printing plate and that when exchanging the stamping plate which, at the same time, is the storage member, the types on the new stamping plate need to be produced anew.
In U.S. Pat. No. 5,855,170 A, a refillable stamp is disclosed in which a stamping plate, a cotton layer and a storage member are introduced in a retaining element. The retaining element is snapped in with an actuating part and displaceable relative to a housing. For refilling ink, the retaining element has two filling sockets. What is disadvantageous with this stamp is that mounting of the stamping plate together with the storage member will cause soiling, as mentioned before.
From U.S. Pat. No. 4,676,162 A, a stamp with a simple rubber stamping plate is known. In this case, the stamping plate is retained in a mount by means of a frame that has snap-in elements. Actuation is effected via a handle which—against the force of a spring—moves the mount with the stamping plate downwards within the stamp housing via a piston so as to produce a stamp imprint on a substrate. A disadvantage is that this stamp cannot be refilled, for which reason the entire stamp, and the stamping plate, respectively, must be exchanged when the stamping ink has been used up.
In U.S. Pat. No. 6,302,022 B1 a hand-operated stamp is shown which is to be considered to be the closest prior art, wherein a storage member is retained in a retaining means together with a stamping plate. These two parts are releasably interconnected via two separate, lateral, spring-mounted snap fasteners. For refilling ink, the latter is supplied via openings in a cover of the retention means. This stamp has, above all, the disadvantage of a complex fastening construction and, associated therewith, an expensive and cost-intensive production wherein, moreover, its handling during the refilling of ink (stamping ink) is cumbersome.